This invention relates to establishment of a telephone connection using Internet protocol (IP) to a station that is not currently connected to the Internet.
Data Network Protocol Telephony, such as Internet Telephony, (otherwise known as IP (Internet Protocol) Telephony) i.e., the routing of telephone calls through the Internet is now possible between two stations, both of which are connected on an active connection to the Internet. However, in the prior art, it is not possible to complete a call to a wireless powered-up station or a land-line station that at the time a call is originated, has no active connection to the Internet. With the increasing prevalence of both Internet service and cellular service, this is a serious limitation.
The above problems are solved, and an advance is made over the teachings of the prior art in accordance with the principles of this invention, wherein in response to a request to establish a data network protocol, such as an Internet Protocol (IP) telephone call to a wireless or wireline station that is not currently connected to the Internet, the station is notified and requested to initiate registration and connection to the Internet; after the station is so connected and registered, the IP telephone call can be completed.
In one specific implementation, if the called station is a wireless station, the wireless station is paged, and the paging message includes an indication that the page request is for an IP telephone call; in response to the paging request, the wireless station initiates a connection to a point of presence, hereinafter called a home agent, for terminating the incoming call within the Internet; the Internet then establishes a connection between the appearance of the incoming call at the input of the Internet, and this home agent. Advantageously, such an arrangement allows a suitably equipped cellular station to receive IP calls, even when the station, though powered-up, is not on an active connection to the Internet.
In accordance with one preferred embodiment of the invention, if the terminating cellular station moves, and attaches itself to a foreign agent, a connection is established within the Internet between the home agent and the foreign agent for communicating with the cellular station. Advantageously, the cellular station may move during the course of the conversation without losing the IP call.
If the called station is a wireline station not currently connected to a point of presence or home agent, the called station is alerted, without establishing a connection to a serving switch, with an indication that the called station should register on the Internet at a home agent for serving the called station. After the called station has registered and is connected to the home agent, the call is completed as in the prior art IP telephony procedures.
If the terminating wireline station has a Personal Computer (PC), there are a number of ways of alerting the PC without establishing a connection. A pre-programmed caller identification can be sent as a caller ID signal, and intercepted in the caller ID unit to generate an appropriate signal to the PC. Called number identification can be used to send either a special called number which can be interpreted by the called number identifier unit of the terminating subscriber as an indication to request a registration on the Internet, or an added number dedicated to this purpose can be used; in the latter case, this added number is stored in either the DDS or the ITHS, and is passed through the PSTN to the called number. A suppressed ringing connection can be used to access a telemetering interface unit, and this telemetering interface unit upon receipt of an appropriate data message can trigger the PC to request registration. If the terminating station is an ISDN, (Integrated Services Digital Network) station, the data message for causing the PC to request an Internet registration action can be passed as a control message over the D-channel. In all of these cases, no connection need actually be set-up in the PSTN; it is adequate if the Common Channel Signaling (CCS7) network of the PSTN, transmits a message that the terminating switch understands and can act upon.
If the called station is a wireline station not currently connected to a point of presence or home agent, the called station is alerted, without establishing a connection to a serving switch, with an indication that the called station should register on the Internet at a home agent for serving the called station. After the called station has registered and is connected to the home agent, the call is completed as in the prior art IP telephony procedures.
In accordance with one preferred embodiment of the invention, the caller need not be a xe2x80x9cdial-upxe2x80x9d Internet station, but can be a wireless, or wireline connected to the Internet via the Public Switched Telephone Network, (wireless or wireline). Such a caller is connected in accordance with the principles of the prior art via an Internet Telephony Gateway, for performing the function of converting between circuit voice signals and IP packets. Other caller terminals may be directly connected via a data access network to a point of presence on the Internet.